Note: Descriptions are shown in the official language in which they were submitted.
S
1 MARKING FOAM SYSTEM FOR AGRI~ULTURAL ~QUIP~E~T
Backyround of the Invention
1. Field of the InventionO
The present invention relates in general to land
- vehicles, and in particular to agricultural vehicles and
systems associated with such agricultural vehicles.
Specifically, the present invention relates to a marking
system for indicating the boundaries oî an area treated by
an agricultural vehicle.
2. Des~ription of the Prior Art.
Modern agricultural science includes the treatment of
large areas for many reasons, such as applying f~rtilizers,
herbicides, insecticides and the like. For many reasons,
including economy, ecology, efficiency and maximized
coverage, it is important that the area being treated be
clearly marked to distinguish the areas that have already
been treated from the areas that have not yet been treated.
E'or this reason, there have been several proposals for
systems that demark and identify areas of treatment by
various agricultural techniques and processes. Some of
these proposals have included mechanical demarcation
devices, and some of the proposals have included spraying
marking foam to form the marking system.
No matter what design is used, however, there are
certain requirements that should be met to ensure that the
marking system is effective for the intended purpose.
For example, the marking system should be amenable to
efficient operation by a minimum number of people. It is
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1 this requirement that often presents drawbacks to the
mechanical systems.
Still further, the marking system should not, itself,
be a source of crop damage. ~ere, also, the mechanical
systems have been found lacking.
The agricultural marking system will be subject to many
~i conditions that may change within a single operation and may
also change from operation to operation. In order to be
most effective, the marking system should be amenahle to
producing a clear marking system under all sorts of
conditions which may be subject to change even within a
single application.
While mechanical systems involving placement of stakes
or the like may be somewhat amenable to providing a clear
marking system each time, such systems are so wast~ful of
manpower and may be so time consuming as to make them
economically undesirable. Coupled with the other
disadvantages of such systems, mechanical marking systems do
not appear to be a viable way of effecting the marking of
areas of treatment.
In view of the shortcomings of mechanical systems,
there have been several proposals for nonmechanical marking
systems. These nonmechanical systems generally involve the
use of marking foam that is sprayed onto the area behind a
motor vehicle.
While somewhat effective in overcoming the just-
mentioned drawbacks asscociated with mechanical marking
systems, the present foam spraying systems have their own
drawbacks.
1 Chief among such drawbacks results from the lacX of
adaptability for these systems. That is, the marking
systems that spray foam onto an area to demark that area are
subject to producing results of varying effectiveness as
conditions change.
For example, as discussed above, it is necessary for
the marking system to provide a clearly evident mark over
the entire range of the area being treated. This mark
should not deteriorate to a level that it cannot be easily
seen by workers at a later time whereby an already-treated
area is re-treated because the markings were not evident
enough. Clearly, to ensure such a situation does not exist,
the marking foam can be made dark and thick enough to
compensate for such a later deterioration of marking foam.
However, such a solution may prove wasteful of marking foam
by making some areas too dark in order to ensure that other
areas have marks that are dark enough to be easily seen.
m is problem of nonevident markings may also occur at or
near the end of a run when the supply of marking foam-
producing material is nearly exhausted.
Another problem associated with the lack ofadaptability of present foam marking systems occurs when
conditions of a run change from earlier conditions within
that run or from conditions existing in a prior run. System
settings may make the marking acceptable for the earlier-
existing conditions, but not for the later-encountered
conditions. This can also be a result of portions of the
dispensing system functioning differently at different
times, for example due to clogging or the like. Present
systems realLy do not have any effective method for
1 accounting for such variation in operating conditions, and
thus, nonuniform markings may result from the present
systems which mark using foam which is applied using a spray
system.
Still further, in order to be most effective, that
portion of the overall system directed to fluid storage
should be designed specifically for fluid storage, and that
portion of the overall system directed to marking foam
production should be designed for such operation. However,
in most of the present systems, one tank is used to both
store and make the marking foam. This requires such a tank
to balance design considerations whereby some storage-
related functions may be less efficient in order to make
foam-making functions viable and vice versa. System
maintenance and cleaning may be difficult in such systems as
well.
Since the final foam-marking product may be dependent
on the ratio of the various components used to form that ;
marking foam and the conditions under which it is formed, to
be most effective, the overall system should include some
means for controlling and varying such parameters as
necessary. However, present systems generally make the
marking foam in a single tank and then dispense that foam
using nozzles or the like. There is no means for varying
the conditions or the ratios, or both, associated with the
making and the dispensing of the final foam-marking
product. The!refore, the final product in most of the
present systems may not have the proper quality to be most
effective for a particular application.
a ~
1 A still further drawback to present systems is the use
of a pump for moving foam through the system. It may be
more efficient to move liquid or a mixture of liquid and
foaming agent by some means, and then to move marking foam
using a motive means that is most efficient in moving such
fluids. Present marking foam systems do not make this
distinction in fluid properties and thus, may not be
efficient as possible.
Therefore, while present marking systems that use
marking foam are successful in overcoming some draw~acks
associated with other systems, the nonadaptability and lack
of efficient foam-forming and moving means of such foam
marking systems may create problems that tend to vitiate the
overall performance of such systems.
Accordingly, there is a need for marking system that
uses marking foam, but which is adaptable and amenable to
changing operation to account for changing conditions to
produce effective markings for all conditions to which the
system may be exposed, and which can be designed to be most
efficient in its overall operation.
~ummary of the Invention
In the practice of the present invention, a foam
marking system is provided which is adapted for use with
agricultural vehicles to indicate the boundaries of treated
areas, which system includes means for quickly and easily
varying the parameters and ratios of the components of the
marking foam being dispensed. ~he system fluidically and
physically separates the ~oam-making elements from the
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1 storage elements, and thus, permits variation of the various
parameters without unduly affecting the other parameters.
In this manner, the marking system can be adjusted to
account for changed conditions .o produce the most effective
and efficient marking. This change can be effected between
runs or during a run if necessary. Still further, due to
this separation of elements, each element can be designed to
accomplish the objectives associated therewith without
sacrificing other objectives and design factors associated
with other functions of the system. This separation of
elements also permits use of pumping devices that are
designed for the most efficient operation of the system and
are not constrained in the manner of many prior art systems.
Specifically, the foam spray marking system embodying
the present invention includes an air compressor and a
storage tank that is adapted to store liquid and a foaming
agent and which is fluidically connected to the air
compressor. The system also includes a mixing control means
which is fluidically connected to the air compressor and to
the storage tank and has means for mixing the compressed air
with the mixture of liquid and foaming agent dispensed from
the storage tank to form a mixture that is usable for
generating marking foam. This mixing control means is
fluidically coupled to a foam tube which converts the fluid
from the mix:ing control means into marking foam.
The mix:ing control means includes means that can adjust
the amount of compressed air being used to form the marking
foam fluid and the amount of liquid/foaming agent being used
in such fluid independently of each other whereby the most
efficient and effective marking foam can be generated in the
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1 foam tube for the particular conditions to which the overall
system is subjected at any particular time during its
operation.
The adjustment means includes a solenoid-operated valve
or a venturi-like fluid mixing chamber wherein compressed
air flows past a dispensing spray nozzle to assist in the
withdrawing of liquid/foaming agent therefrom. The amount
of fluid and the mixing ratios involved can thus be readily
adjusted to meet the exact conditions of the system at
any time.
Further control of the system can be effected since the
system includes control valves and the like which are
situated in the system to effect the most desirable control
over the fluid flowing in the system. The air compressor is
used to drive the liquid mixture ou-t of the storage tank,
and thus, the system embodying the present invention does
not require pumps for moving foam, and the amount of
compressed air flowing to the storage tank can be adjusted
to account for supply depletion in that storage tank without
adversely affecting the ratios and parameters associated
with the making of the marking foam in the foam tube. This
makes the overall system more efficient and reliable than
many prior art systems that rely on pumps to move fluid from
one place in the system to another.
The physical and fluidic separation of the various
components of the system also permit each component to carry
out its intended function in the most effective and
efficient manner, and also permits the system to be easily
and efficiently serviced while also permitting the system to
be modified to account for vagaries in the operation of
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1 individual components, such as might resul-t from the
malfunctioning of one marking foam dispensing nozzle.
Objects of ~he Invention
It is a main object of the present invention to provide
a foam marking system for indicating the boundaries of an
area treated by an agricultural vehicle that is capable of
providing e~ficient and effective markings under all
conditions.
It is another object of the present invention to
provide a foam marking system for indicating the boundaries
of an area treated by an agricultural vehicle that is
capable of varying the parameters affecting the makeup of
the foam dispensed during the operation of the system in a
manner that produces the most effective markings for
a particular application.
It is another object of the present invention to
provide a foam marking system for indicating the boundaries
of an area treated by an agricultural vehicle that has the
components thereof capable of being designed for the most
efficient operation associated with that particular elemen-t.
It is a specific object of the presen-t invention to
provide a foam marking system for indicating the boundaries
of an area -treated by an agricultural vehicle that has the
foam-making ]produc-t storage element separated from and
independent of the foam makeup and foam-forming elements.
It is another specific object of -the present invention
to provide a foam marking system for indicating th~
boundaries of an area treated by an agricultural vehicle
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1 that includes a specific element that can be controlled to
produce marking foam that is most effective for a particular
application and condition.
According to the present invention there is provide a
field spray marking system for indicating the boundaries of
an area treated by an agricultural vehicle comprising: (a)
a compressor means for supplying compressed air; (b) a
storage tank fluidically connected to said compressor means
to receive compressed air therefrom for pressurizing said
storage tank, said storage tank being adapted to store
liquid and foaming agent therein for forming a
liquid/foaming agent mixture and having an outlet through
which said liquid/foaming agent mixture exits from said
storage tank; (c) a solenoid-operated valve fluidically
connected to said storage tank outlet for receiving said
liquidtfoaming agent mixture from said storage tank; (d)
valve operating means connected to said solenoid-operated
valve for operating said solenoid-operated valve; (e) fluid
coupling means fluidically connected to said solenoid-
operated valve for receiving liquid/ foaming agent mixturetherefrom, said fluid coupling means having a chamber and a
spray means for spraying liquid/foaming agent mixture into
said chamber; (f) means fluidically connecting said
compressor means to said fluid coupling means chamber and
conducting compressed air into said chamber adjacent to said
spray means t:o cooperate with said spray means for
controlling 1:he amount of liquid/foaming agent mixture
introduced into said chamber; (g) a foam tube fluidically
connected to said fluid coupling means chamber to receive
liquid/foaming agent mixture and compressed air therefrom
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1 and for converting said mixture and compressed air into
marking foam; and (h) a marking foam dispensing nozzle
fluidically connected to said foam tube to receive marking
foam therefrom.
Also according to the pre~,ent invention thereis
provided a ield spray marking system for indicating the
boundaries of an area treated by an agricultural vehicle
comprising: (a) a compressor means for supplying compressed
air; (b) a storage tank fluidically connected to said
compressor means to receive compressed air therefrom for
pressurizing said storage tank, said storage tank being
a~apted to store liquid and foaming agent therein for
forming a liquid/foaming agent mixture and having an outlet
through which said liquid/foaming agent mixture exits from
said storage tank (c) a mixing control means fluidically
connected to said compressor means to receive compressed air
therefrom and fluidically connected to said storaga tank
outlet to receive liquid/foaming agent mixture therefrom,
and including mixing means mixing compressed air with said
liquid/foaming agent mixture in a controlled amount; (d) a
foam tube having an inlet fluidically connected to said
mixing control means to receive compressed air and
liquid/foaming agent mixture therefrom in controlled amounts
and having means to produce marking foam, and an outlet; and
(e) a marking foam dispensing nozzle fluidically connected
to said foam tube.
Further according to the present invention there is
provided a field spray marking system for indicating the
boundaries of an area treated by an agricultural vehicle
having a compressor means for supplying compressed air, and
1~21 ~0~
1 a storage tank for containing liquid and a foaming agent to
provide a liquid/foaming agent mixture, the improvement in
combination therewith comprising: (a) a foam tube which
converts compressed air and liquid/foaming agent mixture
into marking foam and which is fluidically connected to the
compressor means and to the storage tank; (b) the storage
tank being located fluidically downstream of the compressor
means to receive compressed air therefrom and said foam tube
being located fluidically downstream of the storage tank to
receive liquid/foaming agent mixture therefrom; and (c) a
mixing control means fluidically interposed between the
storage tank and the foam tube and fluidically connecting
the compressor means to the foam tube, said mixing control
means having means for controlling the amount of
liquid/foaming agent supplied to said foam tube and for
controlling the amount of compressed air being supplied to
said foam tube.
Finally, according to the present invention, there is
provided a field spray marking system for indicating the
boundaries of an area treated by an agricultural vehicle
comprising: (a) a compressor means for supplying compressed
air; (b) a storage tank being adapted to store liquid and
foaming agent therein for forming a liquid/foaming agent
mixture and having an outlet through which said
liquid/foaming agent mixture exits from said storage tank;
(c) pump means connected to said storage tank outlet for
pumping said liquid/foaming agent mixture therefrom; (d)
mixing control means including a chamber fluidically
connectad to said compressor means to receive compressed air
therefrom and fludically connected to said pump means to
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1 receive liquid/foaming agent m:ixture therefrom, said mixing
control means including means iEor introducing compressed air
to the chamber, said mixing control means including means
for spraying said liquid/foaming agent into said chamber,
said mixing control means including means for controlling
the mixing of compressed air arqd liquid/foaming agent; (e) a
foam tube having an inlet end with said mixing control means
located thereat, means to produce marking foam, and an
outlet end; and (f) a marking foam dispensing nozzle
fludically connected to said foam tube outlet end.
Other objects and advantages of this invention will
become apparent from the following description taken in
conjunction with the accompanying drawings wherein are set
forth, by way of illustration and example, certain
embodiments of this invention.
The drawings constitute a part of this specification
and include exemplary embodiments of the present invention
and illustrate various objects and features thereof.
Brief Description of the Drawings
Fig. 1 is a perspective view showing the overall system
embodying the present invention mounted on an agricultural
vehicle.
Fig. 2 is a schematic showing the fluid circuit
associated with the foam marking system embodying the
present invention.
Fig. 3 is a perspective view showing the check valve
used in the system embodying the present invention.
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1 Fig. 4 is a side elevational view showiny a foam tube
and mixing control means used in the system of the present
invention.
12a
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1 Fig. 5 is a side elevational view of an alternative
form of the mixing control means used in the system
embodying the present invention
Fig. 6 is a perspective v:iew showing a three-way
control valve used in the system of the present invention.
Fig. 7 is a side elevational view, partially cut away,
showing a marking foam dispensing nozzle used in the system
of the present invention.
Fig. 8 is a schematic showing the fluid circuit
associated with a foam marking system comprising a first
modified embodiment of the present invention.
Detailed ~escription of the Preferred ~mbodimen~s
As required, detailed embodiments of the present
invention are disclosed herein; however, it is to be
understood that the disclosed embodiments are merely
exemplary of the invention, which may be embodied in
various forms. Therefore, specific structural and
functional details disclosed herein are not to be
interpreted as limiting, but merely as a basis for the
claims and as a representative basis for teaching one
skilled in the art -to variously employ the present
invention in virtually any appropriately detailed
structure.
Shown in Fig. 1 is an agricultural vehicle 10, such as
a tractor or the like, which is used in treating areas with
fertilizers, herbicides, insecticides or the like. The
vehicle 10 therefore includes a dispersing system 12 which
is used in the dispersing process. Neither the particular
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1 dispersing system nor the particular agricultural vehicle
form a part of -the present invention, and will thus not be
discussed in greater detail. Elowever, it is noted that the
dispersing system will include the elements usual to such
systems, such as appropriate dLspersing nozzles or the like
which are located with respect to the vehicle to disperse
the material of interest in the most efficient manner.
As discussed above, it is important to mark the
boundaries of the areas treated, and thus, the vehicle 10
includes a spray marking system 14 which is the subject of
the present invention.
As shown in Fig. 1, the marking system 14 includes a
sprayer boom 16 mounted on the vehicle lQ, and which
includes a plurality of sections that are adjustably coupled
together at joints 18. The sprayer boom 16 includes an
upper arm 20 and a lower arm 22 adjustably attached to the
vehicle and each section includes an upper arm, such as
upper arm 24 of outermost section 26, and a lower arm, such
as lower arm 28 of outermost section 26, which are
adjustably connected to the corresponding arms of the next
section by the joint 18.
~ ovement of the sprayer boom 16 with respect to the
vehicle 10 is controlled by the vehicle operator, and the
means for mo~ing such boom can include motors, controls
located to be within easy reach of a vehicle operator
sitting in the cab C of the vehicle and the like, as well as
suitable joints and the like. The manner of moving the
sprayer boom 16 with respect to the vehicle 10 will occur
to those ski]led in the art based on the present disclosure,
and thus wil] not be further discussed.
14
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1 As shown in Fig. 1, the sprayer boom 16 includes a
marking foam dispensing nozzle 30 on one end thereof, and a
second marking foam dispensing nozzle 32 on the o-ther end
of the boom. The dispensing no~zles 30 and 32 are located
to dispense marking foam onto t:he ground at the outer
boundaries of the area treated by the dispensing system 12,
and are supplied with marking foam by the system 14 in the
manner discussed below. The no~zles 30 and 3? are angled
and oriented to dispense markin~ foam in the most visible
manner, and will also be discussed in greater detail below
with regard to Fig. 6.
Referring next to Fig. 2, the marking system 14 forming
the subject of the present invention will be discussed. As
shown in Fig. 2, the marking system 14 includes a compressor
means 40 which is adapted to draw ambient air thereinto,
compress such air to a desired degree, and force such
compressed air out through an outlet line 42. The
compressor means 40 can include the usual elements, and is
driven by a power source, such as a battery pack 44 or the
electrical system of the agricultural vehicle 10, and is
controlled by means of an on/of-E switch 48. The degree of
compression of -the air in the outlet line 42 can be
controlled by a pressure regulator 46 to control the
pressure of the compressed air being supplied to the
remainder of -the system by the compressor means 40 for
purposes of controlling the quality and quantity of the
marking foam dispensed by the system 14, as will be evident
from the discussion presented below~
Compressed air in line 42 flows through the pressure
regulator 46 to a junction means or tank T-coupling 50 which
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1 i5 fluidically connected to a storage tank 52. The junctlon
means 50 includes a pressure gauge 51 which is shown as
being mounted on the junction means 50, but can be mounted
in the vehicle cab C. The gauge 51 provides a visual
readout of the pressure of th~ compressed air being supplied
by the compressor means 40 so that system 12 parameters can
be set to the most desirable values. The junction means 50
will be further discussed below in regard to Fig. 3. I`he
storage tank 52 is adapted to contain liquid, such as water,
and foaming agent, such as is commonly used in field
marking, and has an inlet 54 to which a first outlet 56 of
the junction means 50 is fluidically connected to flow
compressed air into the storage tank in a manner that may be
controlled by a check valve means 55 to pressuri~e the fluid
in the storage tank to a level great enough to provide
sufficient motive force to drive the fluid through the
remainder of the system as will be seen from -the ensuing
discussion. The storage tank also has an outlet 58 through
which a liquid/foaming agent rllixture flows to be used by the
remainder of the marking system 14.
The liquid/foaming agent mixture from storage tank 52
flows via conduit 60 to a mixing control means 70, which
will be further discussed below, and is mixed with
compressed air exiting the check valve means 55 which may be
located in a second outlet 72 of the junction means 50 and
flowing in ccnduit 74 therefrom to the mixing control means
70.
The mixing control means 70 combines compressed air
from conduit 74 with a liquid/foaming agent mixture from
conduit 60 in a ratio and in a manner as set by the
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1 components of the marking system 14 to form a marking foam-
forming mixture. I~he mixing control means 70 is fluidically
connected to an inlet 76 of a foam tube 78 -to conduct this
marking foam-~orming mixture into the foam tube 78. This
marking foam-forming mixture is converted into marking foam
in the foam tube 78 and exits that foam tube 78 via an
outlet 80.
A conduit 82 fluidically connects the foam tube outlet
80 to an inlet 81 of a selecting means 84 which further
includes a first outlet 86 fluidically connected to a
conduit 88 for fluidically connecting foam dispensing nozzle
30 to the foam tube 78 to receive marking foam therefrom,
and a second outlet 90 for fluidically connecting second
marking dispensing nozzle 32 to the selecting means 84 via
conduit 92 whereby, when the selecting means 84 is appro-
priately operated, marking foam from the foam tube 78 is
dispensed to the dispensing nozzle 32.
Operation of the selecting means 84 is controlled to
select nozzle 30 unless a special command is given. ~his
operation is preferably carried out by including a spring
biasing means in the selecting means 84 to bias the outlet
86 into fluid connection with the inlet 81 of the selecting
means 84, and to further include an electromagnetic device
to overcome this spring bias when energized to move the
selecting means 84 to fluidically connect the outlet 90 to
the selec-ting means inle-t 81. Such electromagnetic device
can include an electromagnet in the selecting means 84
connected by a line 91 to a switch 93 that is connected to
the battery pack 44. Operation of the switch 92 energizes
the electromagnet to move the second outlet 90 into fluid
7 ~
1 connection with the inlet 81; whereas, unless the
electromagnet is energized, the selec-ting means 84 will be
spring-biased into a configuration that fluidically connec-ts
the first outlet 86 to the inlet 81. In this manner, the
system can mark an area using either dispensing nozzle 30 or
dispensing nozzle 32 as selected by the operator.
Operation of the marking system 14 is as follows:
ambient air is compressed to a selected pressure by the
compressor means 40 and flows to the storage tank 52 via the
conduit 42, the pressure regulator 46 and the junction means
50 to pressurize the fluid contained in that storage tank.
This pressurized fluid is then forced out of the storage
tank into conduit 60 as a liquid/foaming agent mixture and
moves to the mixing control means 70 to be combined with
compressed air from the check valve means 55 and conduit 74.
The ratios and parameters of the mixing of the compressed
air from conduit 74 and the liquid/foaming agent from
conduit 60 are varied and controlled by the mixing control
means 70 to form a starting material for use in the foam
tube 78 to generate the marking foam ~IF that is most
desirable for a particular application.
As discussed above, the conditions to which the system
14 is exposed may vary from run to run or even within an
individual run, and thus, the abili-ty of the system 14 to
vary the parameters and ratios of the marking foam-
generating mixture permits the system to account for such
changes in conditions.
Having discussed the overall system 14 and its
operation, attention is next directed to Figs. 3-7 for a
discussion of the individual elements of that system.
18
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1 Referring to Fig. 3, the junction means or tank T-
coupling 50 is shown as haviny a coupling ~lanye means 96
for releasably coupling the junction means 50 to the storage
tank 52. This coupling means 96 can include hand-operated
cams or the like. As is also shown in Fig. 3, second outlet
72 of the junction means 50 is fluidically connected to a
valve assembly 98 including a valve T-coupling 99 with an
inlet 100 fluidically connected to the junction second
outlet 72. rrhe valve T-coupling 99 includes a primary
outlet 101 and a secondary outlet 102. The primary outlet
101 is connected to the compressed air conduits 74 via a
nipple 103. The check valve means 55 selectively controls
the flow of air from the primary outlet 101 to the air
conduit 74. rrhe nipple 103 and the check valve means 55 may
be secured in place on the primary outlet 101 by a wing nut
104.
The check valve means 55 can be adapted for delayed
opening when a predetermined pressure level is attained in
the storage tank 52, for example, five pounds per square
ir.ch (psi~. By delaying the opening of the check valve
means 55 and the introduction of compressed air through
compressed air conduit 74 into the foam tube 78, the marking
foam-forming mixture from the conduit 60 can accumulate in
sufficient quantities in the mixing control means 70 to form
markiny foam ME` having the desired properties. Furthermore,
the check valve means 55 may control the air pressure in
compressed air conduit 74 with respect to the pressure in
the storage tank 52, which determines the pressure in the
marking foam-forming mixture conduit 60. E'or example, in
operation the air pressure in the air conduit 74 may be in
19
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1 the range of nine to fifteen pounds per square inch, and the
pressure in the storage tank 5~ may be in the range of
fifteen to thirty pounds per square inch, with the pressure
differential being established by the check valve means 55.
As alternatives to the check valve means 55, various o-ther
flow and pressure regulating devices could be employed in
the valve T-coupling 99 or the compressed air conduit 74.
The secondary outlet 102 mounts a bleeder valve 106
with an open position for communicating the tank 52 with the
atmosphere and a closed position. With the marking system
14 in operation, the bleeder valve 106 is normally closed.
The bleeder valve 106 is used to bleed compressed air from
the marking system 14, and in particular from the storage
tank 52. The bleeder valve 106 may be opened before the
coupling 96 is removed from the storage tank inlet 54 to
prevent the coupling 96 and the various components attached
thereto from being hurled off of the storage tank 52 by the
force of the compressed air therein.
It is also noted that the pressure gauge 51 can include
a remotely located signaling device and/or feedback control
system for further adjusting and controlling the operation
of the system 14. The check valve means 55 can also include
means for automatically opening when the pressure reaches a
predetermined level, such as five psi, seven psi, ten psi,
or the like.
Referring next to Fig. 4, the preferred form of the
mixing control means 70 is shown to include a solenoid-
operated valve 110 fluidically interposed in the conduit 60
between the storage tank 52 and the foam tube 78. The
30 solenoid valve 110 is powered via line 112 connected to the
~L'~ t,-,~
1 on/off switch 4~ to control the flow of fluid in the line
60. By suitably controlling the opening and closing of the
solenoid valve 110, more or less liquid/foaming agent
mixture may be supplied for producing the marking foam
starting agent.
A filter 118 may be fluidically interposed between the
conduit 60 and the solenoid operated valve 110, and a hand
adjusting means 120 can also be included to permit easy
dismantling of the mixing control means 70 for purposes of
cleaning or the like.
Located downstream of the solenoid valve 110 is a
mixing T-coupling 122 having a body 124 adapted to form a
mixing chamber 126 and a first inlet means 128 adapted for
cooperable coupling with the solenoid valve 110 by means of
suitable coupling means, such as nipples, nuts and the like,
to fluidically couple the chamber 126 with the storage tank
52 to receive liquid/foaming agent mixture therefrom. The
mixing T-coupling 122 also includes a second inlet means 130
adapted to be releasably coupled to the compressed air
20 conduit 74 to fluidically connect the chamber 126 to the
compressor means to receive compressed air therefrom.
The mixing control means 70 further includes a spray
nozzle means 134 fluidically coupled to the conduit 60 to
dispense liquid/foaming agent in a spray pattern in the
chamber 126. ~he spray pattern is indicated in Fig. 4 by
the reference indicator S and is directed inwardly of the
chamber 126. The spray nozzle means 134 can be of any
design which is suitable for producing the fan spray pattern
indicated in Fig. 4. The orifices of the spray nozzle means
134 affect its spray pattern S, and spray nozzle means
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1 having various numbers, sizes and configura-tions of orifices
can be chosen to provide desire~d spray patterns of the
liquid/foaming agent. Compressed air from conduit 74 is
directed into the chamber 126 in the direction indicated by
arrow A in Fig. 4, to flow towards the outlet 136 and is
located and adapted to cooperate with the flow of the spray
to combine the compressed air with the fluid in the spray
within the chamber 126. This combination produces a mixture
that flows to the foam tube 78 to be converted into marking
foam in that foam tube 78. For this reason, the mixture
formed in the chamber 126 will be referred to as marking
foam starting mixture.
The foam tube 78 includes means for converting the
marking foam starting mixture into marking foam ~F, and such
means can include steel wool W, Teflon scouring pad
material or the liXe, and various foraminous screens and
layers of material M.
As can be seen from the above, the quality and quantity
of marking foam ME' generated by the foam tube 78 can be
controlled by adjusting the flow of compressed air into the
chamber 126, by adjusting the flow of liquid/foaming agent
mixture via the solenoid valve 110, or by adjusting the foam
tube 78 itself. In this manner, the overall marking foam MF
can be adjusted as necessary. It is also noted that the
flow of compressed air across the spray r.ozzle 134 affects
the amount of fluid dispensed from that nozzle, and the
quality and quantity of marking foam MF produced can also be
altered and controlled by means of the speed and amount of
compressed air flowing across the spray nozzle 134 in a
manner analogous to the conditions exis-ting in a carburetor.
:L ~ 2 ~
In fact, to emphaslze thls feature of the system, attentlon is
dlrected to Flg. 5 whlch shows the carburetor sltuation. It ls
noted that the operatlon of the Flg. 5 element is so simllar to
that of a carburetor that the full dlscussion of carburetor
actlon wlll not be presented, but reference is made to standard
texts, such as "The Internal Combustlon Engine" by Charles F.
Taylor and publlshed by the MIT Press, for a full dlscusslon of
such actlon. It is noted that such dlscusslon of the Taylor
book ls lncorporated hereln by reference thereto. Thus, as
lndlcated ln Fig. 5, the spray nozzle 134 ls replaced by
dlspenslng condult 138 located ad~acent to the throat area of a
venturl-shaped passage 140, and compressed air from condult 74
flows through the passage 140 and past condult 138 to asslst ln
the dlspenslng of fluld from that condult. The compressed alr
mixes wlth the fluld from the condult 138 and forms the marklng
foam startlng mlxture ln chamber 142 that then flows to the
foam tube 78 as indlcated ln Flg. 5 by arrow F.
Referrlng next to Flg. 6, the selectlng means 84 ls
shown ln detall. It ls noted that thls element ls fully
dlscussed ln U.S. Patent No. 3,985,333, asslgned to Spraylng
Systems Co. of Wheaton, Illlnols. The selectlng means 84 ls
descrlbed by the asslgnee* as belng "AA144-1-3 Three-Way
Solenold-Operated Dlrectovalve". When power ls applled to the
selectlng means 84, marklng foam MF ls dlrected to condult 88
and flow to conduit 92 stops; whereas, when power ls off,
marklng foam flows to condult 92 and stops flowlng to condult
88. A cap 144 closes off one condult of the selectlng means.
23
132~ ~Q ~
1 The marking foam dispensing nozzles 30, 32 are
identical, and nozzle 32 is shown in Fig. 7. The marking
foam dispensing nozzles 30, 32 each includes a right-angle
coupling 146 for connection by a hose clamp 149 to a
respective conduit 88 or g2. A flexible connector tube 147
has a proximate end 148 connected to the coupling 146 by a
hose clamp 149, and also has a distal end 150. A nozzle
skirt 151 includes a neck 152 connected to the connector
tube distal end 150 by a hose clamp 149 and a bottom 153
open to an interior 154. The skirt neck 152 extends into
the skirt interior 154 and mounts a foam screen 155 by means
of a hose clamp 149. The foam screen 155 may comprise, for
example, open-woven fiberglass cloth or mesh formed as a
porous, closed-end tube. The foam screen 155 functions to
capture foam as it is dispensed under pressure from a ~.
conduit 88 or 92, and contributes to a certain amount of
back pressure through the conduits 88, 92 in the foam tube
78. Such back pressure may be helpful in forming and
dispensing the marking foam MF. The marking foam MF is :.
forced through the foam screen 155 and may drop in globules
to a field surface for demarcating a boundary of an area
treated by the dispensing system 12. The globules of
marking foam MF may drop at regularly-spaced intervals, or
the marking foam MF may be dispensed substantially
continuously. However, spaced globules are generally :~
sufficient in the field to demarcate a boundary of an area : :
treated by the dispensing system 12.
A foam marking system 160 comprising a first modified
embodiment of the present inven-tion is shown in Fig. 8 and
includes a pump 162 in communication with the liquid foaming
'~
24
~32~
1 agent conduit 60 for pumping liquid foaming agent from the
storage tank 52 to the mixing control means 70. Pressurized
air is communicated from the compressor 40 via the
compressor outlet line 42 to a check valve 164 and thence
via the compressed air conduit 74 to the mixing control
means 70. The foam marking system 160 operates to produce
marking foam ~F in a manner substantially similar to the
marking system 14, except that with the system 160 liquid
foaming agent is pumped from the storage tank 52 to the
mixing control means 70 and pressurized air is communicated
from the compressor 40 to a check valve 164 and then to the
mixing control means 70.
It is to be understood that while certain forms of the
present invention have been illustrated and described
herein, it is not to be limited to the specific forms or
arrangement of parts described and shown.
;`
